The topic of consent in paediatrics is made more difficult, and at the same time more interesting, by the complexity of the issues involved and the consequent diversity of viewpoints. In a teaching session for senior medical students on consent in paediatrics it proved necessary to reinstate previous learning from a range of disciplines. Philosophical medical ethics, developmental psychology, communication skills and the appropriate legal definitions all contributed to a proper understanding of the cases presented. The two most important additional components appeared to be a) a basic knowledge of cognitive development and how to apply it, and b) an awareness of the need to balance an individual child's rights or best interests, with those of the family unit, as well as the wider society.